This invention relates to means and methods of cryogenically storing perishable fluids, and particularly for storing the blood of a donor and accessing the same blood to permit use in behalf of the donor in autogenous blood transfusions.
Cryogenic storage systems conserve perishable commodities such as whole blood, pharmaceuticals, enzymes, semen, living tissues, or other biological specimens by holding them in storage packets arranged in a cryogenic tank at low temperatures for sustained periods. In such systems, removal of a particular blood packet for an autogenous transfusion requires rapid and accurate access to the packet. On the other hand the space in the containers of such systems is precious.
In the part, such systems have been wasteful of space or inefficient in the rapid storage packet. One such system requires removal of many, and in some instances all, of the frozen fluid storage packets out of the cryogenic container to gain access to one packet. Another system requires leaving one sixth of the space in the interior of the cryogenic tank empty to permit shifting a large section of packets into the empty space for subsequent removal of the desired packet. This system requires a complex control arrangement for shifting the packets.